Avy.. hey, when you think about it the AR platform is perfectly sportable, just like the Kalashnikove platform. When you look at it, the darn thing is just a semi-auto rifle that can be had in so many different configurations that sporterization should be considered a natural evolution of that platform.
Go with a nice wood stock, good fitting and functional - black plastic stocks make cowards and liberals crap their pants; same with the pistol grips. Demilitarize the barrel and action - go for a integral magazine or limit the mag to4 or 5 shots, Use sporter sights and dress it for sporter scopes rather than mil-spec stuff. The AR platform will sporterize better than any of the other semi-auto military actions we have used. The aluminum might not take a nice blue but hey.......